Sent to Australia after the Attack on Pearl Harbor, the 41st became one of the first Army units to engage in offensive ground combat operations during World War II when elements of the division were committed to the New Guinea campaign in the last months of 1942.

In the final months of the war, the division took a major role in the liberation of the Southern Philippines, including the Palawan, Zamboanga, Eastern Mindanao and Sulu Archipelago operations.

The division staff, composed of personnel from all five states, came together to conduct joint training for several summers before World War II, usually at Fort Lewis or Camp Murray.

For the 1937 camp, the division participated in the Ninth Corps Area phase of the Fourth Army maneuvers at Centralia-Fort Lewis held in August.

[3]: 1  In 1940, the “Sunset” Division again participated in the Fourth Army maneuvers at Fort Lewis, this time as part of the provisional IX Corps.

[3]: 3  Delayed by strike action at sawmills in Washington and Oregon and by maritime workers, the project fell behind schedule,[6] and the entire division was not accommodated in the new barracks until April 1941.

Large scale maneuvers continued in August on the Olympic Peninsula, with IX Corps defending Tacoma, Washington until the two divisions from California could arrive to assist.

[3]: 17  The 218th Field Artillery had earlier been assigned to the defense of the Philippines, and was at sea en route when news of the attacks came; it was turned back to San Francisco and eventually rejoined the division.

(The others were the 32nd who preceded them into combat on New Guinea; the Americal and the 1st Marine on Guadalcanal, Carlson's Raiders on Makin Island; and the 9th, 3rd Infantry, 34 and the 2nd Armored Divisions who fought in North Africa.)

That month the remainder of the division, including the 186th Infantry and 146th, 205th and 218th Field Artillery battalions entrained at Fort Lewis for San Francisco, from whence they sailed for Australia, arriving on 13 May.

Major General Robert L. Eichelberger, whose I Corps headquarters arrived in Rockhampton in August, ordered the division to commence training in jungle warfare.

The first elements, which included the 1st Battalion and regimental headquarters, flew over the Owen Stanley Range to Popondetta and Dobodura on 30 December, where they came under the command of Australian Lieutenant General Edmund Herring's Advanced New Guinea Force.

[10]: 329–330 The 163rd Regimental Combat Team was attached to Major General George Alan Vasey's 7th Australian Division and Doe assumed command of the positions on the Sanananda track from Brigadier Ivan Dougherty on 3 January 1943.

[10]: 341 The first part of Vasey's plan involved the blocking of the Killerton Trail to prevent the Japanese from using it as an escape route, and to provide a jumping off point for a later advance by the 18th Infantry Brigade.

Taken to 7th Division headquarters for interrogation, the man revealed that the Japanese commander, Lieutenant Colonel Tsukamoto Hatsuo, had ordered all able bodied men to evacuate Perimeter P, leaving the sick and wounded to hold it to the last.

Supported by a troop of the 2/1st Field Regiment and their own mortars, Rankin's 2nd Battalion reduced the three small enemy perimeters to the south of their position and advanced to meet the Australians on the Killerton Track.

The Presidential unit citation awarded the 1st Battalion, 162nd Infantry Regiment, reads "for outstanding performance of duty against the enemy near Salamaua, New Guinea.

Moving inland through deep swamps, crossing swift rivers, cutting its way through dense jungle, over steep ridges, carrying by hand all weapons, ammunition, and food, assisted by only a limited number of natives, this battalion was in contact with the enemy for 76 consecutive days without rest or relief.

Cutting the Japanese supply line near Mubo, exerting constant pressure on his flank, the valiant and sustained efforts of this battalion were in large part instrumental in breaking enemy resistance and forcing his withdrawal from Salamaua on 12 September 1943.

By April 1944, an armada of a hundred ships carrying 25,000 men and tons of equipment had been assembled for an attack on the Humboldt Bay area of New Guinea to secure Japanese-held airfields.

The subsequent explosions ignited a two-day firestorm that consumed all American ammunition and rations landed in that beach area, and caused 24 deaths and over 100 injuries.

Following a naval bombardment on 17 May, the 163rd Infantry landed four companies (A, B, C and F), seized the beachhead and began the push inland assisted by four M4 Sherman medium tanks.

The companies executed a successful flanking maneuver which left the important airfield in the middle of the island in Allied control after only two days of fighting.

The capture of Mokmer Drome was particularly challenging due to the proximity of cliffs of coral that provided very strategic cover for Japanese heavy guns.

Because the 41st failed to repeat the swift progress made in prior landings, General Fuller was relieved as commander of Hurricane Task Force.

[15] The War Department published a postwar policy statement on October 13, 1945 which called for the rebuilding of the Regular Army, National Guard of the United States, and the Organized Reserve Corps.

[16] Preliminary plans for the post-war reorganization of the 41st was to maintain its triangle task organization from the Second World War and proposed it split between Idaho, Oregon, and Washington.

On August 2, 1946, it was announced that General Rilea had been disqualified for military service for medical reasons and the first Division Commander of the 41st since post-war reorganization would go to Washington.

This concept was derived as a means to create five somewhat autonomous elements within a division, called battle groups, that could activate and attack quicker than a brigade as a new strategy to prepare for tactical nuclear warfare.

The veterans had the opportunity to visit Arlington National Cemetery and hold a special wreath laying ceremony at the Tomb of the Unknown Soldier.